Superheater unit



Jan. 19, 1937 w. H. HINSCH SUPERHEATER UNIT Filed May 9, 1935 INVENTORWALTER. Sc.

BY I A'ITORNEY v Patented Jan. 19, 1937 UNITED STATES PATENT OFFICE 9Claims.

This invention relates to improvements in superheater units and itconsists of the matters hereinafter described and more particularlypointed out in the appended claims.

One of the objects of the invention is to provide a superheater unitespecially adapted for use in locomotives and wherein heat units aretransferred to the incoming saturated steam instead of to the outgoingflue gases so that an equalizing action on the thermal loading isafforded and no loss in thermal heat results.

Another object of the invention is to provide a superheater unit whereinthe superheated steam is employed initially to raise the temperature orsuperheat of the incoming saturated steam so that it is in bettercondition for final superheating in its passage through the final steamsuperheating tube of the unit.

A further object of the invention is to provide a superheater unit whichmay be readily substituted for those recognized as standard and now inuse and when so substituted will raise the operating efliciency of thelocomotive.

. Still a further object of the invention is to provide a superheaterunit which is practical to make and install and which is more efficientin operation than other units now used for the same purpose.

In the drawing:

Fig. 1 is a longitudinal horizontal sectional view through a locomotiveflue containing a superheater unit embodying the preferred form of theinvention;

Fig. 2 is a longitudinal vertical sectional View through the locomotiveflue, as taken on the line 2--2 of Fig. 1 and illustrates the improvedsuperheater unit in side elevation; and

Figs. 3, 4 and 5 are transverse vertical detail sectional views on asomewhat enlarged scale (I as taken on the line 3--3, 4-4 and 5-5,respectively, of Fig. 2.

In general, the improved unit includes a saturated steam receiving tubeat the front end through which extends an outgoing superheated steamtube so as to be surrounded by the incoming saturated steam in the firstmentioned tube and which saturated steam receives heat units for initialsuperheating before it receives its final superheating in the tubesprovided therefor. In this manner, there is no heat loss to the gases inthe front end of the flue though there may be a heat transfer from theoutgoing superheated steam to the incoming saturated steam.

Referring now in detail to that embodiment of the invention, illustratedin the accompanying,

drawingboiler secured at its ends in the conventional manner in thefront and rear flue sheets 2 and 3 respectively. 4 indicates, as awhole, the improved superheater unit arranged in said flue. The improvedunit includes an incoming saturated steam tube 5 at the front end of theflue and which tube, as herein shown, is of a cruciform or clover-leafcross section of such diameter as to leave a gas passage space 6 betweensaid tube and the flue I. with radial spacers or supports I to keep itproperly positioned within the flue. At the ends of the tube 5 are frontand rear closure heads 8 and 9 respectively, each having a pair of topand bottom, outwardly extending flanges or collars lO-II and I2-I3respectively.

Within the incoming saturated steam receiving tube 5 is an outgoingsuperheated steam tube, the intermediate portion I4 of which is disposedin the axis of the tube 5 and the ends of which, are offset upwardly tobe secured in the top collars or'flanges I8 and I I of the end heads 8and 9. The collar I I has secured thereto a saturated steam inlet tubeI5 leading from the saturated steam compartment of a superheater headernot shown. The collar I0 also has secured thereto a superheated steamoutlet tube I6 leading to the superheated steam compartment of theheader before mentioned.

In the flue I, rearwardly of the incoming saturated steam tube 5, is thefinal steam superheating arrangement for the unit. This arrangement, asshown herein, is of the so-called double loop tube form and includesfour tube sections I'I, I8, I9 and respectively. The front end of thetube section II is secured in the bottom collar or flange I3 of the tube5 and receives initially superheated steam from the rear end of saidincoming saturated steam tube '5. The rear end of the tube section II isconnected by a bend with the rear end of the tube section I8, the frontend of the last mentioned tube section being connected by a bend withthe front end of the tube section I9. The rear end of the tube sectionI9 is connected by a bend with the rear end of the tube section 20, thefront end of which connects with the inlet end of the outgoingsuperheated steam tube I4. Thus the steam in the tube sections I'I, I8,I9 and 28 is caused to take a tortuous path with resultingcounter-flows.

The group of tube sections II, I8, I9 and 20, which are disposed in therear end of the flue The tube 5 is provided where the highesttemperature prevails, are held in grouped relation by means of a spacerand surrounding band 2l22, the latter including spacer or supports 23 asbest shown in Fig. 3 for holding the said tube sections centrally in theflue i.

In operation, saturated steam enters the tube 5 from the tube 65 andfills said tube 5 and surrounds the tube i l therein. In the passage orflow of the saturated steam through the tube 5 from the front to itsrear end, said saturated steam absorbs heat units from the outgoingsuperheated steam in the tube i l and is initially superheated thereby.As the tube sections ii, H2, H9 and 25 are disposed in the hottest endof the flue l, the steam passing therethrough picks up the heat unitsfrom the hot gases to become superheated. The superh ated steam thenpasses through the tube It and out of the same through the tube E8 tothe superheated steam compartment of the superheater header, not shown.As the outgoing superheated steam passing through the tube it has a muchhigher temperature than the incoming saturated steam in the tube 5, thesaturated steam will absorb heat units therefrom. This heat unittransfer, however, cannot be reckoned as a superheat loss because it isemployed as the initial superheat for the saturated steam which, in turnacts as a heat insulator between the superheated steam and the lowtemperature gases passing out through the front end of the flue. Thuswhen the superheated steam is entirely surrounded by the saturatedsteam, this avoids reheating the flue gases at this point with aresulting loss. Therefore the transfer of heat units from the tube tothe saturated steam does not result in a heat loss but exerts only anequalizing efiect on the thermal loading.

By the use of the saturated steam tube of cruciform or clover-leaf crosssection, the area of each end becomes large enough to receive theassociated pair of tubes and at the same time, the superficial area ofthe tube 5 is increased Without unduly sacrificing gas passage space atthis point. I

It is apparent that instead of the double loop or four section tubesherein shown and described, a tube of the so-called single loop orhairpin type may be employed without departing from the spirit of theinvention.

Preferably in making up the tube 5, the heads 8 and 9 are madeseparately and then welded in place.

The construction described does not require special fittings oralterations to make it possible for substitution in making replacements.The improved construction is simple and efiicient and-can be made inaccordance with present boiler practice.

While in describing the invention, I have referred indetail to the form,arrangement and construction of the various parts thereof, the same isto be considered only in the illustrative sense so that I do not wish tobe limited thereto except as may be specifically set forth in theappended claims.

- I claim as my invention- 1. A superheater unit embodying therein anincoming saturated steam tube, an outgoing superheated steam tube havinga major portion between its ends arranged within the first mentionedtube so as to be surrounded by the saturated steam therein for a directexchange of heat between the outgoing superheated steam and the incomingsaturated steam, and a steam superheating arrangement communicating atits front end with the rear ends of the incoming saturated steamreceiving tube and the outgoing superheated steam tube.

2. A superheater unit embodying therein an incoming saturated steamreceiving tube, an outgoing superheated steam tube arranged axially ofand extending the full length of said incoming saturated steam tube soas to be surrounded by the steam therein for a direct exchange of heatbetween the outgoing superheated steam and the incoming saturated steam,and a steam superheating arrangement communicating at its front end withthe rear ends of the incoming saturated steam tube and the outgoingsuperheated steam tube.

3. A superheater unit embodying therein an incoming saturated steamtube, an outgoing superheated steam tube having its full length portionarranged Within the first mentioned tube so as to be surrounded by thesaturated steam therein for a direct exchange of heat between theoutgoing superheated steam and incoming saturated steam, and a steamsuperheating arrangement connected at its front end to the rear ends ofthe incoming saturated steam tube and the outgoing superheated steamtube, the superheated steam in the outgoing superheated steam tubehaving a flow counter to the incoming saturated steam in the saturatedsteam tube.

4:. A superheater unit embodying therein an incoming saturated steamtube, an outgoing superheated steam tube extending longitudinallythrough the incoming saturated steam tube so as to be surrounded by thesaturated steam therein for a direct exchange of heat between theoutgoing superheated steam and the incoming saturated steam, and aloop-like steam superheating tube connected at its front ends to therear ends of the incoming saturated steam receiving tube and theoutgoing superheated steam tube.

5. A superheater unit embodying therein an incoming saturated steam tubeclosed at both ends and having a pair of tube connections at each end, asaturated steam inlet and a superheated steam outlet engaged in a pairof connections at one end of the tube, a steam superheating tube of loopformation having inlet and outlet ends engaged in a pair of connectionsat the other end of the incoming saturated steam tube, and an outgoingsuperheated steam tube in the saturated steam tube so as to besurrounded by the steam therein and engaged at its ends in saidconnections in which the superheated steam outlet and the outlet end ofsaid loop formation are engaged.

6. A superheater unit embodying therein an incoming saturated steam tubeof cruciform cross section and having a head at each end, an outgoingsuperheated steam tube arranged with the greater portion of its lengthaxially in the incoming saturated steam tube so as to be surrounded bythe saturated steam therein for a direct exchange of heat thereto, theends of said outgoing superheated steam tube being offset and engaged inthe heads of said saturated steam tube, and a steam superheating tubearrangement communicating at its front end with the rear ends of theincoming saturated steam receiving tube and the outgoing superheatedsteam tube.

7. In combination with a boiler flue, means providing an incomingsaturated steam tube in the front end of said flue and separatedtherefrom by an annular flue gas passage, an outgoing superheated steamtube having its full length arranged within the first mentioned tube soas to be surrounded by the saturated steam therein for a direct heatexchange thereto, a saturated steam inlet for said incoming saturatedsteam tube, and a superheated steam outlet communicating with the frontend of the incoming saturated steam tube and the outgoing superheatedinitial steam tube respectively, and a steam superheating tube of loopformation arranged in said flue rear- Wardly of said incoming saturatedsteam tube and communicating at its front ends with the rear ends of thesaturated steam tube and the outgoing superheated steam tube.

8. In combination with a boiler flue, means providing an incomingsaturated steam tube of cruciform cross section in the front end of saidflue and separated therefrom to be surrounded by a gas passage therein,an outgoing superheated steam tube having its greatest length disposedcentrally in said incoming saturated steam tube so as to be surroundedby the saturated steam therein for a direct heat exchange thereto, saidoutgoing saturated steam tube having its ends fixed off-center in theends of said saturated steam receiving tube, a saturated steam inlet anda superheated steam outlet communicating with one end of said incomingsaturated steam tube and with one end of said outgoing superheated steamtube respectively, and a steam superheating tube of loop formationarranged in said flue rearwardly of said incoming saturated steam tubeand l communicating at its front ends with the rear end of the incomingsaturated steam tube and with the outgoing superheated steam tube.

9. In a superheater unit, means providing a tubular body, a head closingeach end of said body and each head having a plurality of openingstherein offset with respect to the axis of said body, a tube in saidbody having a mid portion thereof arranged substantially axially of thebody and having end portions offset axially of the body and each endportion being connected in at least one opening in each head, one end ofsaid tube in one head serving as a superheated steam outlet and theopening in the same head serving as a saturated steam inlet for saidbody, and a conduit member connecting the opening in the other head withthe end of the tube connected in the same head.

WALTER H. HINSCH.

